Flotation machines are typically configured to retain a slurry, or pulp, within a tank. The slurry may include a material that is desired to be extracted from finely sized particles within the liquid of the slurry. The flotation machines are used to separate valuable material such as minerals from material having little or no value by means of changes in the surface chemistry of solid particles in a slurry so that certain particles become hydrophobic or hydrophilic. Examples of flotation machines may be appreciated from U.S. patent application Ser. No. 13/535,566, U.S. Pat. Nos.7,441,662, 5,205,9264, 4,800,017, 4,425,232 and 2,973,095, International Publication Nos. WO 2011/069314 and WO 2011/066705 and Polish Patent No. 64101.
Often, flotation machines utilize a rotor positioned adjacent a stator. The rotor is rotated to agitate the slurry. Bubbles may be formed by agitation of the slurry and the feeding of air into the slurry to cause a froth to form above of the slurry. The hydrophobic particles will attach to the bubbles being carried to the top of the tank of the flotation cell where a froth is formed. The froth and particles suspended in the froth are collected by launders positioned adjacent to the top of the flotation cell.
In some designs, a type of gas such as air may be introduced into the slurry for the generation of bubbles and the formation of a froth. The air or other gas may be emitted so that the rotating rotor agitates the emitted gas along with the slurry to help generate a condition within the slurry to propagate the formation of froth above the slurry. U.S. Pat. No. 4,425,232 may provide one example of such a flotation machine design.
We have determined that it would be desirable to design a new flotation machine such that the stator, rotor, or both the rotor and stator of the flotation machine is configured to provide an improved recovery of material from retained slurry. We have determined that the improved recovery would also be preferably obtained while also reducing the cost of manufacture and the cost of operation associated with the flotation machine.